Circuit making and breaking device



s. B. HUQD CIRCUIT MAKING AND BREAKING DEVICE Deco 119270 ZWAA W mafi m M M m 1. M m J\ I E m m Y m m m Md, 5. m l m 0 m w W w m F k w Pawnee Dec. 20, 1921.

UNITED STA TES Pagan- OFFICE.

f SAMUEIi B. HOOD, F MINNEAPOLIS, MINNESOTA, ASSIGNOR TO LINE MATERIAL COM- IPANY, OF SOUTH MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

f CIRCUIT MAKING AND nn-nenmennvrcn.

Application filed July 31,

the electrodes or stationary contacts pro-' jected-into "the mercury or other liquid to make the circuit, and vice versa, which has proven objectionable, as the arcing, incidental to the breaking of the circuit, gradually consumes the electrodes ortcontacts.

Having the above and other objections in mind, this invention contemplates as one of its objects the provision of a circuit making and bleaking device of the character described wherein the circuit' is made and broken between the body of mercury or other medium'and not by projecting theelectrodes 'thereinto". i

It is another object of thisinvention to provide a circuit making and breaking de vice of the character described wherein the clinging or stretching characteristic of mercury isntilized to procure,the quick breaking of the circuit in which the device is ineluded. I

lhis invent-ion contemplates as another object the provision of a circuit making and breaking device in which a new contact surface is provided each operation and in which the movable contact is maintained in a clean condition by reason of the quick movement thereof under operation,

A further object of this invention resides in the provision of a circuit making and breaking device of the character described 40 in which the electrodes or stationan contacts are of a relatively large area w ereby h an increased displacement capacity is obtained and consequently the volume of mercury necessary is reduced to a minimum.

This invention contemplates as a further object the provision of a deviceof the character described having means for conveniently adjusting the stationary contacts or electrodes to regulate the normal level of the mercury or other medium. i i

It is a further object of this invention to provide a device of the character described which is operable to make the electric circuit in which the same is included upon the displacement ot the mergury or other liquid.

1924. Serial No. 729,306. l

And a still further object of this invention resides in the provision of a device of the character described having provision for its'manipulation from a distant station and which is of compact design to permit its location in any convenient place.

With the above and ther'objects in'view which will appear as the description proceeds, my invention resides in the novel construction, vcombination and arrangement of parts substantially as hereinafter describedandmore particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the lierein disclosed invention ma be made as come within the scope of the claims.

In the accompanying drawing, trated two complete'examples of the physical embodiment of my invention constructed according to the best modes I havt so far devised for the practical'application of the principles thereof, and in which: A

Figure lfis a view of contact "making and breaking device embodying the features of my invention, the same being partly, in vertical section and partly in side elevation;

Figure 2 is a view, partly in section and partly in elevation, taken through Figure l on the plane or the line 2-2;

Figure 3 is a view, partly in section and partly in top plan, taken through' Figure l on the plane of the line 3-3;

Figure 4t is a fragmentary detail view, partly in section an partl in elevation, taken through Figure 3 on t e planeojt the line et-lgand Figure 5 is a view similar to Figure a of a slightly modified type of my invention.

Referring now more particularly to the accompanying drawings, in which like nuameter than" the outer wells. The partition walls 14: separating the wells are slotted or cut away from a point spaced from the hot! 1 tom of the wells to form connecting passages or openings 15, as best illustrated in Figures 1 and 5 and the upper edges of the walls are inclined inwardly and downwardly toward I have illusmerals designate like parts throughout the connected. Each contact plate 16 is provide'd with a threaded opening 19 in axial alignment'wi'th its well and through which a contact stud 20 is threaded with its lower end extended into the well to be immersed in the mercury or other liquid M which substan "tially fills the'wells approximately to the level of the passages 15. The contact studs are preferably of relatively large diameters to give them increased displacement values and thus reduce the volume of liquid necessary for the device.

Mounted on the base 10, over the well 11 with its. tubular core 21 in axial alignment therewith, is a solenoid 22 into which an armature'23 is movable. In that form of my invention illustrated in Figures 1 to 4, the armature 23 is preferably formed of an iron wire core 24 molded in bakelite, or any other suitable material, and has its lower end disposed in the well 11v and enlarged to form a displacing plunger 25.

The wells 11, 12 and 13 are normally filled with mercury or any other suitable liquid as before described, the normal level of which is slight-1y lower than the upper edges 26 of the partition walls 14, but preferably with the lower ends oi the contact studs 20 immersed therein, as a result of which the continuity of the circuit through the conductor or line 18 is broken between the body ofliqui'd M at the partition walls 14 and not at any of the contacts. The weight of the armature 23 and its plunger 25 is such that it normally sinks to the bottom of the central well and displaces the mercury or other liquid therein raising its level to join the liquid in the wells into a single body through the passages 15, as a result'of which the contacts 20 are bridged and the circuit completed through the body of the liquid M.

When it is'desired to break the continuity f, of the circuit, the solenoid 22 is energized bybeing connected with a source of electrical current, as a result of which the armature 23,

' which is normallydisposed below the center of the magnetic force thereof, is quickly moved into the tubular core 21 withdrawing the plunger 25 from the body of mercury, M, permitting the displaced mercury to return to the central well or chamber. The upward movement of the core and plunger under the magnetic influence of the solenoid 22 is arrested by a. cushion spring 27 preferably of the spiral, conical type wound about the core 23 and normally restingon the plunger 2-5,

-solenoid spool when the armature is drawn thereinto.

Upon withdrawal of the plunger 25 in the manner above described, the displaced mercur returns to the central well or chamber an by reason of its stretching or clinging characteristic, holds together over the edges 26 of the partition walls until 'the tension thereonincreases to a predetermined degree, when it breaks or separates at the edges 26 with a snap, producing a quick break in the continuity of the circuit. The inclination of the upper end or edges of the partition walls also facilitates the quick separation of the mercury. This characteristic of the mercury also permits the normal level of the mercury, when the solenoid 22 is energized to withdraw the plunger from the mercury, to be below the edges 26.

This type of contact making and breaking device is designed to maintain the continuity of the line 18 in the event for any reason the control circuit, not shown, of the the event of failure of the control circuit rather than extinguishedat night.

' In that form of my invention depicted in Figure 5, an inverse arrangement is illustrated wherein energization of the solenoid 22 makes the circuit and the deenergization thereof breaks the continuity of the circuit. This is accomplished by constructing the armature 23 and the plunger 25 of a tubular and light construction so that the overall mass is sufficiently light to permit the plunger to normally float with the armature 23 above the center of magnetic force of the solenoid. In this form, energization'of the solenoid 22 draws the armature 23 downwardly to tend to center its metal with respect to the center of magnetic force, forcing the plunger 25 into the body of mercury which overflows over the walls 14 through the passages 15 to make the circuit. As the operation of this type of device, with the exception of that above described, is the same as that of the one illustrated in Figures 1 to 1-, further description thereof is deemed unnecessary.

From the foregoing description taken in connection with. the accompanying drawing it will be readily evident to those skilled in the art to which an invention of this character appertains that I provide an improved contact making and breaking device which is of very compact construction, which eliminates the arcing due to the breaking of the current, which may be controlled at any distant point, which break the circuit by separation of the liquid contact thus affording a new contacting surface each operation and eliminating injury to the contacts by the destructive arcing incidental to the breaking v of :an electrical circuit, and one in" which the 7 member, the upper portions of the partition walls separatmg the chambers being cut away to provide passages connecting the chambers, a liquid in the chambers, the liquid in th chambers being normally separated by the partition walls, contact plates closing the upper ends of the outer chambers, contact studs threaded in the'contact plates and passed into the outer chambers, and means adapted to displace theiliquid in the central chamber to raise the level thereof above the passages in the partition walls to join with the liquid in the outer chambers and electrically bridge the contact studs." I

2. An appliance of the character described, comprising a base member of insulatingmaterial, a central chamber formed in the base member, outer chambers formed in the base member, the upper portions ot the partition walls separating the\ chambers being cut away to provide passages connecting the chambers, a liquid in the chambers, the liquid in the chambers being "normally separated by the'partition Walls, contact plates closing the upper ends of the outer chambers, con- .tact studs threaded in the contact plates and passed into the outer chambers,said contact studs being of a diameter sufiicient to substantially fill the outer wells to increase their displacement capacity, and means adapted to displace'the liquid in the central chamber to raise the level thereof above the passages in the partition walls to join with the liquid in the outer chambers and electrically bridge the contact studs.

3. An appliance of the character described,

comprising a base member of insulating material, a central chamber formed in the base member, outer chambersformed n the base member, the upper portions of the partition walls separating the chambers being cut away to provide passages connecting the chambers, a liquid inthe chambers, the liquid in the chambers being normally separated by the partition walls, contact plates closing the upp'erends of the outer chambers, contact studs threaded inthe contact plates and passed into the outer chambers, and means adapted to displace the liquid in the central chamber to raise the level thereot above the passages in the'partition walls to join. with the liquid in the outer chambers and electrically bridge the contact studs, the up- I per edges of the partition, Walls being i clined downwardly and inwardly toward the central chamber to rovide a relatively narrow edge overwhich the liquid separates upon withdrawalof the displacing means to thus disconnect the contact studs.

4. An appliance of the character described,

comprising a chamber, mercury in said chamber, an electrical circuit, contacts in said circuit and adapted to be electrically bridged to complete the circuit by the mercury upon raising of its level a' predetermined degree, means operable to displace the mercury and raise the level thereof, and

ing ot-the mercury, means operable-to'dis place the mercury and raise the level thereot beyond normal, and means for adjusting the degree the contact is immersed in the mercury whereby the mercury normal level may be adjusted.

6, An appliance of the character described, comprising a base member, a central chamber formed in the base member outer chamhers formed in the base member, mercury in the chambers and normally divided into separate bodies by the dividing walls of the chambers, an electrical circuit, contacts projected into the mercury and includedin the circuit and adapted to be electrically bridged ice to complete the circuit by raising of the mercury level to join the several bodies, means operable to displace the mercury and raise'the level thereof, contact studs adapted to be partly submersed in the mercury, at all times, and means whereby the normal level of the mercury may be adjusted by the degree the contacts are projected into the mercury. V

7; An appliance of the character described, comprising a base member, a central chamber formed in the base member, outer chambers formed in the base member, mercury in 1 the chambers and normally divided into separate bodies by the dividing walls of the chambers, an electrical circuit, contacts projected into the mercury and included in the circuit and adapted to be electrically bridged to complete the circuit by raising of the mercury level to join the several bodies, means operable to displace the mercury and llll raise the level thereof, contact plates covering the outer chambers, and contact studs adapted to be partly submersed in the mercury, at all times, and having a threaded engagement with the contact plates whereby the normal level of the mercury may be ad justedrby the degree the contacts are proj e into the mercury, I

8. A11 appliance of the character described, comprising a base member, a central chamber formed in the base member, outer. chambers formed in the base member,mercury in 5 the chambers, an electrical circuit, contacts included in the circuit and adapted to be electrically bridged to complete the circuit upon raising of the mercury level a premember of insulating material, and an armature embedded in the displacement member and adapted to be attracted by the solenoid. In testimony whereof I affix my signature.

SAMUEL B. HOOD. 

